This invention relates to a shield that can be emplaced around a bomb or other munition-containing explosive for purposes of preventing an explosive reaction in the event a bullet or fragment or other high velocity body impacts the shield.
A variety of armor systems have been developed for shielding bombs and other munitions from being impacted by high velocity bodies, thereby preventing a detonation or other explosive reaction by virtue of stopping the body from reaching the surface of the munition. The methods and apparatus employed in these armor systems are various. Some armor systems use a single layer of reinforced material. See, e.g., U.S. Pat. No. 848,024 to Gathmann. Others use multiple layers of one or more materials. See, e.g., U.S. Pat. No. 4,664,967 to Tassdemiroglu. Still others use tilted layers of one or more materials. See, e.g., U.S. Pat. No. 3,636,895 to Kelsey. In all the above instances cited, the primary objectives of these variations in the design features of the armor system are to minimize weight of and/or space required for the armor system, while still preventing impact on the surface of the munition being protected.
With the same objective of minimizing weight penalties, shields have been developed that do permit impacts on the surface of the munition, but these shield limit the impact conditions in order to prevent an explosive reaction. One shield of this type, called the diverter, prevents reactions by diverting fragments in order that they impact the munition at grazing angles of obliquity. Other impact-permitting shields employ soft buffer materials that do not generate high enough impact pressures to cause explosive reactions. This invention is an impact-permitting shield that employs mechanisms that limit the duration of pressure transmitted to the explosive, to the extent that not enough energy is delivered to the explosive to cause an energetic reaction. The shield consists of a cylindrical shell emplaced around the munition, and the basic duration-limiting mechanism is a pointed or wedge-shaped protuberance between the interior surface of the shield's shell and the surface of the munition, with the sharp contact touching the munition. Explanation of the physics of how the sharp contact reduces the duration of shock wave loading during an impact will be made later.